Massively parallel propositional reasoning

Boots – shoes – and leggings

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

3642747, 3642768, 3642745, 3649723, 364DIG1, 364DIG2, G09C 0000, G10L 0000

Patent

active

050880489

ABSTRACT:
Propositional reasoning is performed on a massively parallel processor, with sets of element value combinations being handled by separate processing units. A host processor operates as a problem solver generating requests for propositional reasoning, and also operates as an interface between the problem solver and the parallel processor. In response to a request that includes a formula, the interface provides one or more formulas such as justifications and class restrictions. The interface provides instructions to the parallel processor based on each of these formulas. The instruction based on each formula are provided so that the set of element value combinations handled by each processing unit is not divided or forked into two subsets until necessary. If possible, forking is avoided by forcing the value of an element to the only value consistent with the current formula. Furthermore, if no additional processing unit is available for forking, the current formula is kept on a queue of formulas, and the corresponding instructions are subsequently repeated. In this manner, the host processor orders the formulas into a sequence that reduces the number of processing units required. When necessary, a selected assumption is forced to one value to free processing units; its other value is considered subsequently by backtracking. Each element value is assigned one or more bit positions in each processing unit, but when the values in all the processing units are the same for a given element, its bit position may be reclaimed, to reduce memory requirements. The interface also responds to a request for results by sending instructions that use circuitry in the parallel processor to obtain a combined result from the processing units.

REFERENCES:
patent: 3987286 (1976-10-01), Muehldorf
patent: 4468736 (1984-08-01), Desantis et al.
patent: 4675829 (1987-06-01), Clemenson
patent: 4773038 (1988-09-01), Hillis et al.
patent: 4814973 (1989-03-01), Hillis
patent: 4918621 (1990-04-01), Nado et al.
patent: 4949243 (1990-08-01), Ali et al.
Charles J. Petrie, Jr., "A Diffusing Computation for Truth Maintenance", Proceedings of the 1986 International Conference on Parallel Processing.
de Kleer, Johan, "An Assumption-based TMS", Artificial Intelligence, vol. 28, 1986, pp. 127-162.
de Kleer, Johan, "Extending the ATMS", Artificial Intelligence, vol. 28, 1986, pp. 163-196.
de Kleer, Johan, "Problem Solving with the ATMS", Artificial Intelligence, vol. 28, 1986, p. 197-224.
Vilain, M., "Heterogenous Concurrency in a Parallel Truth Maintenance System", Proceedings, 1988 Spring Symposium Series, Stanford University, Mar. 22-24, 1988, pp. 237-242.
de Kleer, J. and Reiter, R., "Foundations of Assumption-Based Truth Maintenance Systems: Preliminary Report", Proceedings of the National Conference on Artificial Intelligence, Seattle, Wash., Jul. 1987, pp. 183-188.
Charniak, E. and McDermott, D., Introduction to Artificial Intelligence, Addison-Wesley, Reading, Mass., 1985, pp. 255-270.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Massively parallel propositional reasoning does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Massively parallel propositional reasoning, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Massively parallel propositional reasoning will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-785963

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.